Hi John,
Thanks for alerting us to this on Twitter—the reappearance of this thread had passed me by, for which I apologise.
Using your test code I’m able to see events working in IE8, 9 and 10 (Windows XP and Windows 7) but IE11 on Windows 8.1 is as you describe, not throwing an event. I’ve tried the Flash update that @darao_donnell mentions below and that also hasn’t helped, so we’re going to have to spend a bit of time looking deeper.
IE has been a bit of a troublesome child with cross-window messaging for all time, and it’s entirely viable that a new security policy change has broken the messaging codepath again.
I don’t have an estimate on how long it’ll take to figure out where the break is yet, so in the interim I will note that the click event for the Intent does still fire (it originates in the same document) and you might be able to use that as a reliable fallback in the interim.
Thanks,
Ben